Newly retired women have been urged to check their state pension entitlements as thousands could be in line for a savings boost if they paid the ‘married woman’s stamp’ in the last 35 years.

Under the old state pension system, some married women that did not work paid reduced contributions as they were expected to depend on their husbands in retirement.

At its peak in 1977/78, around 4.4 million women in the UK were paying the reduced stamp, which was scrapped the following year.

However, those already doing so were allowed to continue paying the reduced rate, which continues to this day.

Royal London has called on women that may have paid the ‘married woman’s stamp’ in the last 35 years to check their state pension as they would be entitled to a concession from the government.

The rate payable would be a full ‘basic’ state pension of £129.20 if they are now divorced or widowed or 60 per cent of the ‘basic’ state pension (£77.45 per week) if they are married.

The government estimated that around 10,000 women could potentially benefit.

A freedom of information request from Royal London revealed that there are still around 200 women in the UK paying national insurance at the reduced rate.

The concession was offered as, before April 2016, women could claim a partial state pension based on the national insurance record of their husband.

However, the new state pension system is based on an individual’s own national insurance record, which could have disadvantaged women who were expecting to claim based on their husband’s record but suddenly could not do so.

Commenting on the findings, Royal London director of policy, Steve Webb, said: “It is amazing that in designing a state pension system in the 21st Century, the government had to include special rules to protect women affected by a rule designed in the 1940s.

“It is not widely known that women who paid the reduced stamp at any point in the 35 years before they retired, and who come under the new state pension system, can claim a minimum payment under the new system.

“If any woman is getting a substantially reduced amount from the new state pension she should check if she paid the reduced stamp and contact the Pension Service if she is in any doubt”.

HMRC said that there could still be some women left paying the reduced rate until the second half of the 2020s.